Latin: Sarcoptes scabiei
The small itch mite is one of the most hated pests as it attacks and lives in the skin of humans as well as a wide variety of animal species all over the globe. The itch mite also goes by the Latin name Sarcoptes scabiei. In Denmark, there are about 6000 cases of itch mites a year. Most cases are registered in the period October-November.
Appearance
Itch mite can be a major nuisance. But the little mite is difficult to spot with the naked eye. It is only between 0.2 and 0.4 millimeters long, which is why you rarely see it. The suspicion of itch mite is only aroused when the first symptoms of its presence occur.
Cases of itch mites were previously reported by doctors to the National Board of Health. From these reports, we know that there are most cases in October-November. In Denmark, there are about six thousand cases of itch mites a year.
Biology and behavior
The itch mite is not a nice acquaintance as it lives by eating the stratum corneum of the skin. When infected with itch mites, it is because a newly fertilized itch mite female has found its way to the skin. The mite is comfortable in places on the skin where the skin is thin and wrinkled, and here it then begins to dig in. Such an “excavation” lasts about an hour.
Once the itch mite has found its way into the skin, the whole big work begins. And in the following months until its death, it will work its way further and further in through the skin parallel to the skin surface. The itch mite only digs a few millimeters forward every day, but every day it lays 2-3 eggs in the skin at the same time. When the eggs hatch, the small larvae begin to dig their own small passages.
The mating between the sexually mature male and female mites takes place in a fold of skin on the skin surface, where they meet. When the mating is over, the female is, as described, ready to go out to make her own itch mites on the unsuspecting host, which she fills with eggs. The life cycle of itch mite is not long but lasts only about 14 days.
Damage
An itch mite can cause some pain and discomfort to its host. But it can also be easily transferred from host to host. This happens especially through direct body contact, such as intercourse. But it is also not uncommon for such a transfer to occur indirectly through clothing or bedding. For instance, infants can contract scabies mites by lying in a bed that has been used by a person with scabies, or through contact with a parent with scabies. Furthermore, it is also not unheard of for itch mites to be transmitted between pets and humans who have close contact.
Itch mites are highly contagious. And if people, patients or nursing staff at a hospital or other institution are affected by itch mites, an explosive spread of the mites can occur between the different groups. This type of aggressive attack is called “crusty scabies” or “institutional scabies”.
The general scabies itching is felt in these places, which probably do not correspond to the places where the mites are most. (after Mellanby)
The infection is best transmitted if you are in prolonged contact with the infected person, or if they are contracted in hot and humid conditions. You can therefore not be infected with the itch mites “on the go”, such as by a handshake, a fleeting cheek kiss or by borrowing an infected person’s newspaper.
There is reason to believe that people with a weakened immune system may be at greater risk of becoming infected with the itch mite. Studies suggest that especially older people or people with a serious immune-deficient disease such as cancer or AIDS will be more likely to develop scabies.
The itch mite has poor conditions if it cannot find new skin to dig into. And if it is in a dry area with high temperatures, it dies by itself within a few hours. In humid and cool places, on the other hand, it can stay alive for a few days.
Prevention and pest control
The itch mite is controlled by treating the infected person as soon as possible. The treatment is simple and can be bought over the counter at the pharmacy. The treatment consists of a lotion that is applied to the skin. Remember to follow the instructions for use carefully. If there are several in the household, everyone should undergo the treatment at the same time. This ensures that the itch mites do not survive by living on another family member.
This is followed by a thorough vacuuming of the home and cleaning and washing of sheets, bedding, underwear, clothing, and other types of textiles that the infected person has been in contact with. Certain types of clothing cannot be washed. These are put in the freezer for a day or two, which will get rid of the itch mites. It is customary to contact people you have visited within the last three weeks and inform them of the outbreak of itch mites. They may be at risk of becoming infected. The same applies to the children’s school, after school care, nursery, or kindergarten, where the children have undoubtedly had close contact with other children, who may therefore be infected.